Gemstone



FIG. 1 is a top plan view of a gemstone according to my new design;

FIG. 2 is a front elevational view thereof, the rear view being a mirror image;

FIG. 3 is a bottom plan view thereof; and,

FIG. 4 is a right side elevational view, the left side being a mirror image. 

The ornamental design for a gemstone, as shown and described. 